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From:   Kuniyuki Iwashima <kuniyu@amazon.com>
To:     <leitao@debian.org>
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Subject: Re: [PATCH net-next] net: Use _K_SS_MAXSIZE instead of absolute value
Date:   Wed, 19 Jul 2023 10:04:45 -0700
Message-ID: <20230719170445.30993-1-kuniyu@amazon.com>
In-Reply-To: <20230719084415.1378696-1-leitao@debian.org>
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From: Breno Leitao <leitao@debian.org>
Date: Wed, 19 Jul 2023 01:44:12 -0700
> Looking at sk_getsockopt function, it is unclear why 128 is a magical
> number.
> 
> Use the proper macro, so it becomes clear to understand what the value
> mean, and get a reference where it is coming from (user-exported API).
> 
> Signed-off-by: Breno Leitao <leitao@debian.org>
> ---
>  net/core/sock.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/core/sock.c b/net/core/sock.c
> index 9370fd50aa2c..58b6f00197d6 100644
> --- a/net/core/sock.c
> +++ b/net/core/sock.c
> @@ -1815,7 +1815,7 @@ int sk_getsockopt(struct sock *sk, int level, int optname,
>  
>  	case SO_PEERNAME:
>  	{
> -		char address[128];
> +		char address[_K_SS_MAXSIZE];

I guess you saw a bug caught by the fortified memcpy(), but this
doesn't fix it properly.

I'll post a series soon that fix the issue and another realted one.

Thanks!


>  
>  		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
>  		if (lv < 0)
> -- 
> 2.34.1